Control mechanism for combination flap and aileron for airplanes



Dec. 8, 1942. B. STINSON 2,304,487 CONTROL MECHANISM-FDR COMBINATION FLAP AND AILERON FOR AN AIRPLANE Filed Nov. 20, 1939 I Zfi i'. 5v

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, INVENTOR Patented Dec. 8, 1942 CONTROL MECHANISM FOR. COMBINATION FLAP AND AILERON 1.01. B. Stinson,

FOR AIRPLANES Jackson Heights, N. Y., assignor to Stinson School of Aviation, Inc., Long Island City, N. Y., a. corporation of New York ApplicationNovember 20, 1939, Serial No. 305,341

3 Claims. (Cl. 244- -83) This invention relates to airplane construction, :and is particularly concerned with the control of theailerons mounted in the wings.

In his previous application, filed October 27, 1939, Serial No. 301,527, applicant set forth a differential arrangement for controlling the ailerons to eliminate the unfavorable yaw occurring when :a plane is banked for turning, and the present invention while using this same arrangement provides a further development whereby theailerons may be moved equally and simultaneouslywithout disturbing the differential control. Although in the application referred to above applicant set :fortha method for the elevating control of the ailerons which was independent of the differential control, this present application combines the two controls into one, in a very simple manner.

In certain straight flying, or particularly upon landing, the pilot will need to'move his ailerons equally and uniformly so as to change the shape of the wings. For instance, in landing, the pilot would want to droop the ailerons of both wings so as to increase the lift of the wing or wings while the plane is decreased in speed. At the same time, in making turns, the pilot would want to use the differential mechanism in order to operate one aileron more than the other.

The present invention relates to the combination of these two movements into a simple arrangement which is very effective and easy to operate.

In order to more clearly disclose the invention, reference is made to the. accompanying drawing, in which:

Figure 1 is a diagrammatic perspective view showing the ailerons connected to the control mechanism. v

Figure 2 is a diagrammatic perspective view showing the ailerons connected by a push-pull method to the control mechanism.

Figure 3 is a diagrammatic perspective view showing the arrangement as in Figure 1, but with an additional offset control shaft.

Similar reference numerals refer to similar parts throughout the drawing.

. plane.

tached of control In the drawing, 1 and 2 are the ailerons. 3 and 4 are torque tubes to which the ailerons are rigidly attached. 5 and 6 are arms attached rigidly to the torque tubes 3 and 4 respectively. The arms 5 and 6 terminate in universal joints 5a and 6a which in turn engage connecting rods 1 and 8, which are in turn attached to plate It at universal joints I! and 18. The plate It is rigidly attached to shaft I2. The shaft [2 is mounted at its forward end in swivel bearing I3,

moves pivot point the wing and deflects free to rotate, attached to the fuselage of the The rear end of the shaft I2 is mounted in bearing I4, and is free to rotate therein. At-

to bearing I4 is an arm 31 which has a pivot point 32 attached to bell crank 33. Bell crank 33 pivots on a bearing pin 34 attached to the fuselageof the plane. The other pin 35 of the bell crank is attached to rod 36, which at its other extremity attaches to lever 31. at pivot point 38. The leveri31 is pivoted to the fuselage at pivot point 39, and terminates in handle 40 which is provided with a spring catch 4| adapted to engage quadrant 42. Quadrant 42 is rigidly attached to the fuselage.

In FigureZ, exactly the same connections are made-through the rods. 1 and 8 which are at.-

.tachedto the controlrods operating the ailerons I and 2. However, in Figure 2 a push-pull type for the ailerons is used instead of the torque tube form as shown in Figure 1.

In Figure 3, the same arrangement is shown as in Figure 1, with the exception that an additional offset shaft 23 with control stick I9 is provided, for operating the plate Hi. The shaft 20 is mounted in suitable the fuselage of the plane, and has a lever 22 rigidly attached thereto which is connected by rod 24 to the plate Is at the universal joint 43. It will be noted that the lever 22 is longer than the distance of point 43 from the center of shaft 12. This is for the purpose of increasing the movement of the ailerons with respect to the movement required of control stick l3. 7

In operation, the pilot is at his controls and desires to droop his ailerons uniformly prior to landing. To do this, he merely pushes handle 40 forward which pivots on pivot point 39 and 33 rearward, thereby moving rod 36 rearward and point 35 in bell crank 33 rearward. Bell crank 33 pivots on point 34 and raise point 32 upward. Pivot point 32 in moving upward raises bearing l4 upward, thereby tilting the entire shaft I2 upward. This forces rods 1 and 8 upward, arms 5 and 6 upward, and rocks torque tubes 3 and 4 towards the rear of ailerons I and 2. Obviously, a reverse motion of the handle 40 toward the rear would tilt the ailerons upward through the v same mechanism.

On landing the airplane the nose is tilted up and it'is possible to increase the lift by drooping the ailerons simultaneously to the point of stalling, and should the lateral equilibrium of the air planeat that point be disturbed by a gust of wind or other cause, it becomes very necessary to have NT CFFIQE bearings attached to the differential control of the ailerons to be able to balance or level the plane laterally.

It'is possible to reach a position where further drooping of the aileron on the low side does not add additional lift and may even cause the lift to diminish. In this event the diiferential action increases the raising of the opposite aileron and thereby depresses the wing,'correcting and levelling the airplane laterally.

This application is a continuation in part of application Serial No. 301,527, filed October 27, 1939.

Having described the invention, what is claimed as new and is desired to be secured by Letters Patent is:

1. In an airplane comprising a fuselage, a pair of wings attached thereto, a pair of ailerons set in the trailing edge of the said wings; a pair of rotatable shafts similarly mounted in each of the wings and rigidly attached at their outer ends to the ailerons, a pair of operating levers rigidly attached to each of the inner ends of the respective shafts, a rotatableshaft pivotally mounted at its forward end in the fuselage, a cross bar rigidly mounted on the said shaft, manual means to rotate the shaft, a bell crank pivotally mounted in the fuselage, one end of said bell crank being pivotally connected to the rear end of said rotatable shaft, a quadrant lever'pivotally mounted in the fuselage, and a connecting link joining the other end of said bell crank and said quadrant lever, and independent tie rods connecting the ends of said levers with the extremities of said cross bar.

2. In an airplane comprising a fuselage, a pair of wings attached thereto, a pair of ailerons set in the trailing edge of said wings; a pair of rotatable shafts similarly mounted in each of the wings and rigidly attached at their outer ends to the ailerons, a pair of operating levers rigidly attached to each of the inner ends of the respective shafts, a rotatable shaft pivotally mounted at its forward end in the fuselage, a cross plate rigidly mounted on the said shaft, manual means'to rotate the shaft, a bell crank pivotally mounted in the' fuselage, one end of said bell crank being pivotallyv connected to the rear end of said rotatable shaft, a quadrant lever pivotally mounted in the fuselage, and a connecting link joining the other end of said bell crank and said quadrant lever, and independent tie rods connecting the ends of said levers with the extremities of said cross plate.

3. In an airplane comprising a fuselage, a pair of wings attached thereto, a pair of ailerons set in the trailing edge of the safd wings; a pair of rotatable shafts similarly mounted in each of the wings and rigidly attached at their outer ends to the ailerons, a pair of operating levers rigidly attached to each of the inner ends of the respective shafts, a rotatable shaft-pivotally mounted at its forward end in the fuselage, an offset cross plate rigidly mounted on the said shaft, manual means to rotate the shaft, a bell crank pivotally mounted in' the fuselage, one end of said bell crank being pivotally connected to the rear end of said rotatable shaft, a, quadrant lever pivotally mounted in the fuselage, and a connecting link joining the other end of said bell crank and said quadrant lever, and. independent tie rods connecting the'ends of said levers with the extremities of said offset cross plate.

JACK B. STIN SON. 

